src/tooltips/ktooltipwindow.cpp

   1 /*******************************************************************************
   2  *   Copyright (C) 2008 by Fredrik Höglund <fredrik@kde.org>                   *
   3  *   Copyright (C) 2008 by Konstantin Heil <konst.heil@stud.uni-heidelberg.de> *
   4  *   Copyright (C) 2009 by Peter Penz <peter.penz@gmx.at>                      *
   5  *                                                                             *
   6  *   This program is free software; you can redistribute it and/or modify      *
   7  *   it under the terms of the GNU General Public License as published by      *
   8  *   the Free Software Foundation; either version 2 of the License, or         *
   9  *   (at your option) any later version.                                       *
  10  *                                                                             *
  11  *   This program is distributed in the hope that it will be useful,           *
  12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of            *
  13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the             *
  14  *   GNU General Public License for more details.                              *
  15  *                                                                             *
  16  *   You should have received a copy of the GNU General Public License         *
  17  *   along with this program; if not, write to the                             *
  18  *   Free Software Foundation, Inc.,                                           *
  19  *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA                *
  20  *******************************************************************************/
  21
  22 #include "ktooltipwindow_p.h"
  23
  24 #include <kcolorscheme.h>
  25 #include <kwindowsystem.h>
  26
  27 #include <QPainter>
  28 #include <QVBoxLayout>
  29
  30 KToolTipWindow::KToolTipWindow(QWidget* content) :
  31     QWidget(0)
  32 {
  33     setAttribute(Qt::WA_TranslucentBackground);
  34     setWindowFlags(Qt::ToolTip | Qt::FramelessWindowHint);
  35
  36     QVBoxLayout* layout = new QVBoxLayout(this);
  37     layout->addWidget(content);
  38 }
  39
  40 KToolTipWindow::~KToolTipWindow()
  41 {
  42 }
  43
  44 void KToolTipWindow::paintEvent(QPaintEvent* event)
  45 {
  46     Q_UNUSED(event);
  47
  48     QPainter painter(this);
  49
  50     QColor toColor = palette().brush(QPalette::ToolTipBase).color();
  51     QColor fromColor = KColorScheme::shade(toColor, KColorScheme::LightShade, 0.2);
  52
  53     const bool haveAlphaChannel = KWindowSystem::compositingActive();
  54     if (haveAlphaChannel) {
  55         painter.setRenderHint(QPainter::Antialiasing);
  56         painter.translate(0.5, 0.5);
  57         toColor.setAlpha(220);
  58         fromColor.setAlpha(220);
  59     }
  60
  61     QLinearGradient gradient(QPointF(0.0, 0.0), QPointF(0.0, height()));
  62     gradient.setColorAt(0.0, fromColor);
  63     gradient.setColorAt(1.0, toColor);
  64     painter.setPen(Qt::NoPen);
  65     painter.setBrush(gradient);
  66
  67     const QRect rect(0, 0, width(), height());
  68     if (haveAlphaChannel) {
  69         const qreal radius = 5.0;
  70
  71         QPainterPath path;
  72         path.moveTo(rect.left(), rect.top() + radius);
  73         arc(path, rect.left()  + radius, rect.top()    + radius, radius, 180, -90);
  74         arc(path, rect.right() - radius, rect.top()    + radius, radius,  90, -90);
  75         arc(path, rect.right() - radius, rect.bottom() - radius, radius,   0, -90);
  76         arc(path, rect.left()  + radius, rect.bottom() - radius, radius, 270, -90);
  77         path.closeSubpath();
  78
  79         painter.drawPath(path);
  80     } else {
  81         painter.drawRect(rect);
  82     }
  83 }
  84
  85 void KToolTipWindow::arc(QPainterPath& path, qreal cx, qreal cy, qreal radius, qreal angle, qreal sweeplength)
  86 {
  87     path.arcTo(cx-radius, cy-radius, radius * 2, radius * 2, angle, sweeplength);
  88 }
  89
  90 #include "ktooltipwindow_p.moc"